For Fx Series Plc; For Fx 3G Series Plc - Mitsubishi Electric FX3G User Manual

FX /FX /FX /FX /FX
3S 3G 3GC 3U
FX -2AD-BD (2-channel Analog Input)
3G
2.3.2 For FX Series PLC
3G
1. A/D conversion and special data register update timing
A/D conversion is performed at every scan time of the PLC.
During execution of END instruction, the PLC performs A/D conversion, reads out the A/D converted data,
and then writes the data in the special data registers.
2. A/D conversion during PLC STOP
Even if the PLC is stopped, A/D conversion will be performed and the special data registers will be updated.
3. If two analog expansion boards are connected
During execution of the END instruction, data will be read out from all the connected boards (in the order of
board A → board B).
4. A/D conversion speed (data update time)
During execution of END instruction, the A/D converted data of all 2 channels will be read out in 180 μs, and
the data read out will be written to the special data registers.
END instruction execution time will be "180 μs × number of connected analog boards."
D-10
PLC User's Manual - Analog Control Edition
3UC
A/D conversion Digital value
start command reading
A/D
conversion
180 s
/2ch
FX -2AD-BD
3G
Board A
FX Series PLC
3G
Sequence Program
END instruction
A/D conversion
start command
A/D
conversion
180 s
/2ch
FX -2AD-BD
3G
Board B
2 Specifications
2.3 A/D Conversion Time
Digital value
reading